Influence of organised scaring on distribution and habitat choice of geese on pastures in Northern Norway
2005
Tombre, I.M. | Madsen, J. | Tommervik, H. | Haugen, K.P. | Eythorsson, E.
Animals' habitat choices are often difficult to evaluate in nature due to the influence of various environmental factors, including human impact. In the present study we evaluate how such impacts influence habitat selection and local distribution of pink-footed geese Anser brachyrhynchus staging in Northern Norway during spring. In recent years, geese have been scared by farmers who protect their cultivated properties. We identified and classified various habitats by satellite images and field survey. Comparing data gathered in years before and during periods of intensive scaring enable us to evaluate how such disturbance influences habitat selection in geese. The scaring activities were recognised at three levels; no scaring, occasional scaring and intensive scaring, the latter representing repeated scaring during the complete 24 h cycle. Based on area estimations of the various habitat types in each scaring category, it appeared that the farmers primarily protected habitats of highest quality and, as a consequence, geese were more frequently registered at less productive habitats. This represents a contrast to the undisturbed situation some years earlier, where geese distributed evenly on the various field habitats. If the future agricultural policy continues towards an increased intensive agricultural practice, farmers may carry on to protect their intensively managed fields and geese will be banished to less productive farmland. Such polarisation will eventually reduce the carrying capacity for geese, creating a situation where they are unable to move freely to exploit resources of crucial importance for migration and reproduction.
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